MT8880 and line connection.

[homith]

Hi everybody! i'm working about MT8880 and I get some problems :
-How to connect DTMF to telephone line?
-When i send DTMF to telephone line, I used oamp LM324 and transformer. But i see the signal drops dracticly.
I don't know how to resolve this problem.
Pls help me to be deal with this problem.
Thank you very much.
Note : contact me to address : bill_homith@yahoo.co.uk